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A309312
Areas of Heronian triangles that uniquely define the lengths of the triangle's sides.
1
6, 30, 42, 54, 66, 72, 114, 132, 150, 198, 204, 234, 294, 306, 378, 390, 408, 468, 486, 522, 570, 594, 648, 684, 726, 744, 750, 798, 816, 876, 984, 1014, 1026, 1110, 1170, 1218, 1254, 1290, 1332, 1350, 1368, 1428, 1494, 1518, 1548, 1554, 1590, 1734, 1770, 1782, 1806, 1938, 1950, 1974
OFFSET
1,1
COMMENTS
These are not necessarily primitive Heronian triangles. The corresponding sequence for primitive Heronian triangles is neither a subset nor a superset of this sequence.
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..10000 (first 500 terms from Jacob Vecht)
EXAMPLE
A triangle with integer sides and an area of 42 square units necessarily has sides 7,15,20, so 42 is a term. 12 is not a term because an area of 12 could have sides 6,5,5 or 8,5,5.
CROSSREFS
Subsequence of A188158.
Sequence in context: A003062 A327157 A336216 * A101937 A101939 A290466
KEYWORD
nonn,easy
AUTHOR
Jacob Vecht, Jul 22 2019
EXTENSIONS
Corrected 37th term "1248" to "1254".
STATUS
approved